[anbast]

False positive MGUS?

by anbast on Fri Aug 22, 2014 12:50 am

Hi,

I was diagnosed with MGUS about 6 months ago when I had a work-up for a fever of unknown etiology, although in the end my doctor thought I had a primary Epstein-Barr infection.

I had an M protein of 1.0 on two separate PEPs. I asked the doctor if she thought the gamma spike could be due to the infection, because I was really sick for an extended period of time, but she said it was not related. Then this week I had my first follow-up testing and there was no evidence of a monoclonal spike! My PEP was completely normal.

Has anyone heard of this happening? I know that the levels can go up and down but I haven't read about anyone getting a completely normal result.

I don't want to get my hopes up that it has gone away and was related to what was going when I was sick.

Thanks!

[anbast]

Re: False positive MGUS?

by anbast on Fri Aug 22, 2014 12:09 pm

Hi,

I forgot to add that I also had a serum Immunoelectrophoresis two times when I was sick in January that also showed a monoclonal spike. These were the results:

IgA 179 mg/dL (40 - 375)
IgG H 1850 mg/dL (600 - 1600)
IgM H 240 mg/dL (30 - 190)

IEP INTRP RSLT INTERP
Monoclonal IgG Lambda type.

PEP INTERP SEE NOTE
Spike in Gamma Region.

My serum Immunoelectrophoresis was also completely normal this time! All the testing has been done at the same lab. I actually work for the organization and am confident with the lab quality.

Any thoughts on this will be greatly appreciated!

[ADUK]

Re: False positive MGUS?

by ADUK on Sat Aug 23, 2014 8:52 am

I think that very small paraproteins can be transient and associated with infections, so it may have disappeared. Or it may just be that it's so small that sometimes it shows up and sometimes doesn't.

I hope it is gone for good

[anbast]

Re: False positive MGUS?

by anbast on Sat Aug 23, 2014 12:30 pm

Thanks, ADUK! I am hoping it is gone for good too.

Because it was odd that the spike went away completely they review my serum immuno­electro­phoresis and reinterpreted it this way:

IgA 162 mg/dL (40 - 375)
IgG 1440 mg/dL (600 - 1600)
IgM 156 mg/dL (30 - 190)

IEP INTRP RSLT
Possible Monoclonal IgG Kappa Type.

PEP INTERP SEE NOTE
Very Small Homogeneous Band in Gamma Region.

I am wondering if this is because my IgG in general was elevated while I was sick it looked like I had a bigger monoclonal spike than I really did, or maybe it is what you said, ADUK, and it was transiently higher. They also described it as a IgG lambda type in my other tests, so that also makes this confusing!

If this has happened to anyone else I would love to hear what happened over time and if anyone has any suggestions of other tests that can be done to clarify the result that would be great.

Thanks!

[Multibilly]

Re: False positive MGUS?

by Multibilly on Sat Aug 23, 2014 2:09 pm

I believe that the IEP (aka IFE or Immunofixation) is the most accurate of all the serum tests for telling you if a monoclonal protein is present or not in your blood. The IEP won't tell you about the specific quantity of M protein that may be present, but it is very good at telling you whether any is present at all.

[Dr. Adam Cohen]

Re: False positive MGUS?

by Dr. Adam Cohen on Sun Aug 24, 2014 9:01 pm

As ADUK mentions, transient small M-spikes or alterations in the free light chains can occasionally be seen on SPEPs during, or shortly after, acute infections, and then resolve.

Hopefully this is what happened in your case, but it is worth following up again in 3-6 months with repeat testing to make sure.

Best of luck with your next tests, and please let us know how they go.

[anbast]

Re: False positive MGUS?

by anbast on Sat Aug 30, 2014 1:14 pm

Thanks so much for the responses! It's been very helpful. I am going to request repeat testing in 6 months and hopefully the results will be reassuring again next time.

[anbast]

Re: False positive MGUS?

by anbast on Sun Apr 12, 2015 12:44 pm

Hi,

I thought I would give people follow-up on my next set of testing. I was actually planning on waiting a year to be retested because I find it stressful to do the testing and the M spike was so low that they couldn't even quantify it. Then I developed numbness in my heels and I started worrying that it was related.

Luckily, the results were essentially the same as in August, which was a relief. I still don't really have an answer about why it hasn't completely gone away if it was related to the infection I had last year, but I'm hoping that it means my risk for progression to multiple myeloma is quite low. It is something I can't completely get out of my mind, though, because both my mother and maternal grandfather died of the condition.

[Gtex]

Re: False positive MGUS?

by Gtex on Sat May 16, 2015 5:38 pm

Have just had a follow up with my haematologist after being diagnosed with mgus. For quite a few months I have been poorly with an acute virus. The blood tests this time came back completely normal with no evidence of paraprotein at all. The consultant suggested that the virus perpetuated the paraprotein to appear in the blood and now the virus has gone so has the paraprotein. Strange. Going to be monitored every six months. This MGUS is a really unusual and unpredictable scenario.

[LuckyMe]

Re: False positive MGUS?

by LuckyMe on Wed Apr 13, 2016 12:52 am

Hi.

I also had an MGUS scare that now seems to be false.

It was also following a two-week illness that included fever, fatigue, and thirst. My family insisted I go to the doctor because it was so unusual for me to be sick for more than a day or two. I was diagnosed with the MGUS and it was suggested I have a marrow test, which I refused. My last blood test showed no sign of the elevated protein levels.

Not only did our family doctor make a huge deal about the last test, he mentioned it in front of my daughter and badly scared her. I was furious. I am 60 and in excellent health, and I plan to avoid doctor visits, as I always have.